A color photographic material comprises at lease one silver halide emulsion layer containing a color coupler provided on a support. The silver halide emulsion layer is a hydrophilic colloidal layer. The color coupler is a water-insoluble and oil-soluble compound. Accordingly, the color coupler cannot be solved in a silver halide emulsion, in which silver halide grains are dispersed in an aqueous gelatin solution. The color coupler has been dispersed in the silver halide emulsion layer using a high boiling organic solvent or a surface active agent.
The color coupler must be finely and uniformly dispersed in the emulsion layer to obtain a clear color image. The high boiling organic solvent has been usually used to disperse the color coupler finely and uniformly in the emulsion layer. In more detail, the color coupler has been contained in particles (or droplets) of the high boiling organic solvent. The particles are dispersed in the emulsion layer.
However, the high boiling organic solvent causes some problems in a photographic material. The solvent tends to ooze out from the surface of the photographic material. Further, the organic solvent softens the silver halide emulsion layer. Furthermore, the color coupler is sometimes crystallized in the solvent. The crystallized coupler cannot form a clear color because its reactivity is poor.
In preparation of the silver halide photographic material, a coating solution of a silver halide emulsion layer is sometimes stored. In the coating solution, droplets of the high boiling organic solvent containing a color coupler are dispersed in a silver halide emulsion. The droplets have been sometimes coagulated or precipitated while storing the coating solution. The coagulated or precipitated particles cause problems when coating the solution or filtering the solution. The problems are also caused by the high boiling organic solvent.
Therefore, it is theoretically preferred to disperse the color coupler finely and uniformly in the emulsion layer without use of a high boiling organic solvent. However, it was practically difficult to do so without the organic solvent.
By the way, U.S. Pat. No. 5,264,333 (Yamanouchi et al) discloses a silver halide photographic material having at least one hydrophilic colloidal layer containing a dispersion obtained by emulsifying and dispersing a solution containing at least one oil-soluble dye and at least one water-insoluble, organic solvent-soluble polymer having at least one repeating unit represented by the following general formula (I): ##STR2## wherein R.sup.1 represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a halogen atom; R.sup.2 and R.sup.3 may be the same or different and each represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; L represents a bivalent bonding group; and n1 represents 0 or 1.
The objects of the invention of Yamanouchi et al are to provide a silver halide photographic material which selectively dyes a specific layer and is excellent in decolorizability or an ability of dissolving-out in processing stages (cf., Yamanouchi et al at column 3, lines 35 to 41).
The oil-soluble dye functions as an antihalation dye or an antiirradiation dye, which does not concern a color image formed from a color coupler. Therefore, the dye must be decolorized or dissolved out in processing stages. The above-defined polymer has an excellent function of decolorizing or dissolving out the oil-soluble dye.
On the other hand, the color coupler and the color image formed from the coupler should not be decolorized nor dissolved out in processing stages. Therefore, it has been considered that the above-defined polymer cannot be used in dispersing a color coupler in a silver halide emulsion layer.